Apparatus and method for voice recognition and displaying of characters in mobile telecommunication system

ABSTRACT

An apparatus and method for speech recognition and character displaying in a mobile telecommunication system. In a speech recognition and character displaying apparatus for a mobile phone, an RF Module processes a signal received from a base station or to be transmitted to the base station by radio, a speech/character conversion table has conversion data for use in converting voice data to character data, a speech recognition and character conversion unit converts the voice signal received, from the base station to voice data using speech recognition and the voice data to character data by referring to the speech/character conversion table, a display displays the converted character data, and a controller provides overall control to the mobile phone, transmits a speech recognition notification request message to the base station in a speech recognition and character display mode, and controls the speech recognition and character display operation.

PRIORITY

This application claims priority to an application entitled “Apparatusand Method for Voice Recognition and Displaying of Characters in MobileTelecommunication System” filed in the Korean Industrial Property Officeon Aug. 30, 1999 and assigned Serial No. 99-36377, the contents of whichare hereby incorporated by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates generally to a service providing apparatusand method in a mobile telecommunication system, and in particular, to aservice providing apparatus and method for receiving a voice signal in atelecommunications system.

2. Description of the Related Art

A mobile telecommunication system includes a base transceiver system(BTS) responsible for radio communication with mobile stations, a basestation controller (BSC) for controlling the BTS, a mobile switchingcenter (MSC) for establishing a transmission/reception path for data andcontrol signals between the BSC and the PSTN (Public Switched TelephoneNetwork), and a base station manager for operating andmaintaining/repairing the BTS and the BSC. The components above comprisea unit of the system where each unit performs its unique functions andcommunicates messages over a network connecting the units which togethercomprise the mobile telecommunication system.

The MSC connects a call from a mobile subscriber to the PSTN so that themobile subscriber can communicate with subscribers of the PSTN or ofother mobile telecommunication networks. The MSC also manages thelocation information of serviced subscribers and collects billing data.The BSC processes traffic including control information, voice signals,FAX data, and Internet data in relation to a call from the subscriber toprovide services to the subscriber terminal. The BTS controls radioresources, receives a radio signal generated from the subscriber,transmits the radio signal via land lines, converts a signal receivedthrough the land lines to a radio signal, and transmits the convertedradio signal to the subscriber. The mobile station is a subscriberterminal for transmitting/receiving voice signals, FAX data, andInternet data via allocated radio resources.

Operational components within the unit systems include an MMP (MSC mainprocessor) provided to the MSC, an LMU (Location Management Unit) formanaging subscriber information, a PIU (PSTN Interface Unit) forinterfacing with the PSTN, a BMP (BSC Main Processor) provided to theBSC, an ATU (Air Termination Unit) for interfacing with a mobile stationin a radio environment, a TCU (Transcoder Unit) for converting voiceinformation in the radio environment to the form of information eligiblefor the PSTN, an IAU (Internet Access Unit) for interfacing with theInternet, an IWF (InterWorking Function) for packet data, a BCC (BTSCall Control) provided to the BTS, and a BRC (BTS Resource Control) forallocating radio channel resources.

When a mobile phone rings upon receipt of a call, it is automaticallyset in a speech state. When it is inconvenient or obtrusive for a userto answer the call, like at a conference or a movie, the user simplyhangs up or turns off power to the phone.

However, a caller may continue attempts to complete the call, toconverse with the user as soon as possible, without knowing theunderlying reasons for the users unavailability. Meanwhile, the user hasno way of ascertaining the urgency of the missed call.

Typically in such a case, the caller will record his message or leavehis phone number via a voice mail service. A disadvantage of the voicemail service is that the caller must wait for the user to check hisvoice mail and respond to the recorded message. Both parties are, inmany cases, reluctant to use the voice mail service due to theinconvenience of leaving and retrieving messages using a key pad.Callers may repeatedly attempt calls relating to urgent matters,prompting the user to either turn off their mobile phone or obtrusivelyanswer the call in a public place.

As stated above, a short message service (SMS) requires that the userexperience the inconvenience of creating a message using keys.Furthermore, when the mobile phone rings upon receipt of a call, itautomatically enters a speech state. The user either hangs up or turnsoff the phone if he is not accepting calls at that particular time.

SUMMARY OF THE INVENTION

It is, therefore, an object of the present invention to provide anapparatus and method for recognizing speech, converting a voice signalto characters, and displaying the characters on a mobile phone in amobile telecommunication system.

It is another object of the present invention to provide an apparatusand method for allowing a caller to transfer his message to a calleduser at any time regardless of the situation of the user.

It is still another object of the present invention to provide anapparatus and method for allowing a user to recognize a message from acaller via a display on his mobile phone when he is not available foranswering the call in a mobile telecommunication system.

It is a further object of the present invention to provide an apparatusand method for recognizing speech, converting a voice signal tocharacters, and displaying the characters on a display in a mobiletelecommunication system.

It is yet another object of the present invention to provide anapparatus and method for transmitting a paging message to acorresponding mobile phone, transmitting a speech recognition andcharacter display function notifying message to a caller in relationwith the paging message upon receipt of a speech recognition andcharacter display request message, applying speech recognition andcharacter data conversion to a voice signal, and character dataconversion, and transmitting the converted character data to thecorresponding mobile phone in the form of a short message.

The above and other objects of the present invention can be achieved byproviding an apparatus and method for speech recognition and characterdisplaying in a mobile telecommunication system. In a speech recognitionand character displaying apparatus for a mobile phone, an RF Moduleprocesses a signal received from a base station or to be transmitted tothe base station by radio, a speech/character conversion table hasconversion data for use in converting voice data to character data, aspeech recognition and character conversion unit converts the voicesignal received from the base station to voice data using speechrecognition and the voice data to character data by referring to thespeech/character conversion table, a display displays the convertedcharacter data, and a controller provides overall control to the mobilephone, transmits a speech recognition notification request message tothe base station in a speech recognition and character display mode, andcontrols the speech recognition and character display operation.

According to another aspect of the present invention, in an apparatusfor speech recognition and character displaying for a base station in amobile telecommunication system, a radio MODEM processes a signalreceived from a mobile phone or to be transmitted to the mobile phone byradio, a speech/character conversion table has conversion data for usein converting voice data to character data, a speech recognition andcharacter conversion unit converts the voice signal to voice data byspeech recognition and the voice data to character data, referring tothe speech/character conversion table, and a controller allocates radioresources, performs call processing along with a corresponding unitsystem like another base station or a mobile switching center, controlsthe speech recognition and character conversion operation, and transmitsconverted character data in the form of a short message to a mobilephone.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and other objects, features and advantages of the presentinvention will become more apparent from the following detaileddescription when taken in conjunction with the accompanying drawings inwhich:

FIG. 1 is a block diagram illustrating a mobile phone in a mobiletelecommunication system according to a preferred embodiment of thepresent invention;

FIG. 2 is a flowchart illustrating a speech recognition and characterdisplaying method in the mobile phone according to the first preferredembodiment of the present invention;

FIG. 3 is a block diagram illustrating a speech recognition andcharacter displaying portion of a base station in the mobiletelecommunication system according to another preferred embodiment ofthe present invention; and

FIG. 4 is a flowchart illustrating a speech recognition and characterdisplaying method in the base station according to the second preferredembodiment of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Preferred embodiments of the present invention will be describedhereinbelow with reference to the accompanying drawings. In thefollowing description, well-known functions or constructions are notdescribed in detail to avoid obscuring the invention in unnecessarydetail.

FIG. 1 is a block diagram of a mobile phone in a mobiletelecommunication system according to a preferred embodiment of thepresent invention.

Referring to FIG. 1, a controller 110 provides overall control to theoperation of the mobile phone. A memory 140 includes a ROM (Read OnlyMemory) for storing an operating program, an EEPROM (ElectricallyErasable and Programmable ROM), and a RAM (Random Access Memory). Thememory 140 stores a program for controlling speech recognition andcharacter data conversion in the mobile phone according to the preferredembodiment of the present invention and has a conversion table referredto for converting voice data to character data.

A display 120 displays the status of the mobile phone or the operationstatus of a program under the control of the controller 110. The displayalso displays a message from a caller in the form of character data anda speech recognition and character display menu according to theembodiment of the present invention. The display 120 is preferably anLCD (Liquid Crystal Display).

A key pad 130 has a plurality of digit keys and function keys andoutputs key input data to the controller 110 in response to userinteraction. The key pad 130 may have a function key with which thespeech recognition and character conversion function is implemented.

A speech recognition and character conversion unit 150 converts a voicesignal to voice data and the voice data to character data, referring tothe conversion table stored in the memory 140 under the control of thecontroller 110 according to the embodiment of the present invention.

An RF (Radio Frequency) module 160 upconverts the frequency of a signalreceived from an analog baseband unit 170 and transmits thefrequency-upconverted signal to a base station (not shown) via anantenna 190 under the control of the controller 110. The RF module 160also downconverts the frequency of a signal received via the antenna 190and outputs the frequency-downconverted signal to the analog basebandunit 170 under the control of the controller 110. The analog basebandunit 170 outputs a signal received from the controller 110 to the RFmodule 160. The controller 110 subjects a digital signal received fromthe analog baseband unit 170 to channel demodulation and channeldecoding. The controller 110 also outputs corresponding voice data to avoice signal processor 180. The voice signal processor 180 converts thevoice data to an audible voice signal via compression/decompression.

The voice signal processor 180 converts a user voice signal receivedfrom a microphone to voice data, compresses the voice data, and feedsthe compressed voice data to the controller 110. The controller 110subjects the voice data to channel coding and channel modulation andtransmit the modulated signal to the base station via the analogbaseband unit 170, the RF module 160, and the antenna 190.

The controller 110 communicates messages with the base station. Thecontroller 110 also controls each component of the mobile phone inrelation to a paging message received from the base station andtransmits a reverse connect order to the base station upon receipt ofsome user key data. The controller 110 transmits a speech recognitioninformation request message and a speech recognition request message tothe base station according to the embodiment of the present invention.

The controller 110 interfaces with the user via the keypad 130 anddisplay 120. The controller 110 displays menus on the display 120 toallow the user to select a function from a corresponding menu. Thecontroller 110 displays the speech recognition and character displayfunction menu on the display 120 according to the embodiment of thepresent invention.

According to the first embodiment of the present invention, the mobilephone may add the speech recognition and character display function menuto a main menu, so that the user can quickly and easily select the menuand function when he is not going to be available for answering a calls.

Upon receipt of a paging message, the mobile phone can set a ring typeto an alarm mode or a vibration mode as is the case for the conventionaltechnology. Alternatively, the mobile phone may be restricted to lampblinking and the displaying of character data on the display, to notifya user of an incoming call.

FIG. 2 is a flowchart illustrating a speech recognition and characterdisplay method in a mobile communication system according to the firstembodiment of the present invention.

Referring to FIG. 2, upon receipt of a paging message in step 210, thecontroller 110 determines whether predetermined key data has beenreceived from the user in step 220. If the predetermined key has beeninput, the controller 110 transmits a reverse connect order message tothe base station in step 230. In step 240, the controller 110 transmitsa speech recognition notification request message requesting that thebase station inform a caller of a speech recognition and characterdisplay service to allow the caller to record his speech message. Then,the base station recognizes the speech recognition and character displaymode of the mobile phone and transmits a pre-recorded correspondingvoice information message to the caller. For example, the voiceinformation message can be “The called party is not available. Leaveyour message and it will be delivered to the called party in a shorttext message immediately”.

In accordance with the first embodiment of the present invention, thecontroller 110 controls the speech recognition and character conversionunit 150 to recognize speech of the caller and converts the speech tovoice data and in turn the voice data to character data in step 250. Instep 260, the controller 110 displays the caller's message in the formof the character data on the display 120. The controller 110 mayrespectively receive the caller's phone number when the caller intendsto leave it and display the phone number data additionally on thedisplay 120 in step 260.

Steps 210 to 240 are performed commonly in the first and secondembodiments of the present invention. Step 250 of speech recognition andcharacter conversion is implemented in the mobile phone or the basestation according to a corresponding embodiment. In the secondembodiment, the mobile phone transmits a speech recognition notificationrequest message instead of the information request message to the basestation, requesting that the base station implement speech recognitionand character conversion. The speech recognition request message will bedescribed again later.

In a CDMA (Code Division Multiple Access) mobile telecommunicationsystem, a short message and a voice signal can be transmitted on thesame channel. Therefore, the base station need not open a new channelfor receiving the phone number data from the caller.

Alternatively, in the second embodiment of the present invention, thebase station performs the speech recognition and character conversionoperation. To do so, the base station includes at least a speech andcharacter recognition unit and a speech/character conversion table.

FIG. 3 is a block diagram of a speech recognition and character displayportion of the base station in the mobile communication system accordingto the second embodiment of the present invention.

Referring to FIG. 3, a controller 330 provides overall control of theoperation of a base station 310. Particularly, the controller 330allocates radio resources and performs call processing together with acorresponding unit system, such as another base station or an MSC.

Upon receipt of a voice signal through an antenna 370, a radio MODEM 320processes the voice signal under the control of the controller. A speechrecognizer 340 recognizes a voice signal from a caller or his speech andoutputs corresponding voice data. A character converter 350 converts thevoice data to character data referring to a speech/character conversiontable 360 stored in memory. The controller 330 transmits the characterdata in the form of a short message to the mobile phone of a calledparty. The called party's mobile phone displays the message from thecaller on the display.

While speech recognition and character data conversion of a voice signalreceived from the radio MODEM 320 has been described in the embodimentof the present invention shown in FIG. 3, the input voice signal mayalso originate from a corresponding mobile telecommunication unitsystem.

FIG. 4 is a flowchart illustrating a speech recognition and characterdisplay method in the base station for the mobile telecommunicationsystem according to the second embodiment of the present invention.

Referring to FIG. 4, the base station transmits a paging message to acorresponding called mobile phone in step 410 and receives a reverseconnect order message from the mobile phone in step 420. The mobilephone preferably performs steps 210 to 230 of FIG. 2 here.

In step 430, the base station receives a speech recognition notificationrequest message from the mobile phone according to the embodiment of thepresent invention. The base station recognizes a speech recognition andcharacter data display mode of the mobile phone and transmits apre-recorded corresponding voice information message to the caller toallow the caller to record his message by voice in step 440. The voiceinformation message may be “The called party is not available. Leaveyour message and it will be delivered to the called party immediately”,for example.

When the caller selects speech recording, the base station performs thespeech recognition function, that is, the base station recognizes thespeech of the caller and converts the voice data to character data instep 460 and transmits the character data in the form of a short messageto the corresponding receiving mobile phone in step 470. Consequently,the receiving mobile phone displays the message from the caller on itsdisplay even during a mode when voice calls are not accepted by theuser.

Meanwhile, the base station may optionally receive the phone number ofthe caller, at the caller's request. The base station transmits thephone number data in addition to the character data to the receivingmobile phone in step 470. Because a short message and a voice signal canbe transmitted via the same channel in a CDMA mobile telecommunicationsystem, the base station need not open a new channel for receipt of thephone number data from the caller.

As noted from the above description, a voice signal is subjected tospeech recognition and character data conversion and the convertedcharacter data is displayed on a mobile phone in the speech recognitionand character displaying apparatus and method according to theembodiments of the present invention. The operation of the speechrecognition and character data conversion may be implemented by themobile phone or a base station.

Upon receipt of a paging message, the mobile phone does not enter avoice call mode if it is in a speech recognition and character displaymode and transmits a speech recognition notification request message orspeech recognition request message to the base station. Then, the basestation or the mobile phone implements the speech recognition andcharacter data conversion. The mobile station displays a speech messageof a caller in the form of character data on a display.

As described above, the present invention is advantageous in that theinconvenience of writing a message using a key pad, as is the case forthe prior art, is eliminated since a voice signal is subjected to speechrecognition and character data conversion and converted character datais displayed on a mobile phone. Furthermore, upon receipt of a pagingmessage, the mobile phone does not enter a speech state and the basestation or the mobile phone implements the speech recognition andcharacter data conversion. Then, the mobile station displays a speechmessage of a caller in the form of character data on a display so thatthe speech message can be delivered to a called at any time regardlessthe availability of the called party.

While the invention has been shown and described with reference tocertain preferred embodiments thereof, it will be understood by thoseskilled in the art that various changes in form and details may be madetherein without departing from the spirit and scope of the invention asdefined by the appended claims.

1. An apparatus for speech recognition and character displaying in acalled party mobile phone for receiving an incoming call from a callingparty in a mobile telecommunication system, comprising: an RF Module forprocessing an RF signal received from a base station; a memory storing aspeech/character conversion table having conversion data for use inconverting voice data to character data; a speech recognition andcharacter conversion unit for converting a voice signal received fromthe base station to voice data using speech recognition and forconverting the voice data to character data by referring to thespeech/character conversion table; a display for displaying theconverted character data; and a controller for providing overall controlto the mobile phone, transmitting a speech recognition notificationrequest message to the base station if the called party mobile phone isin a speech recognition and character display mode upon receiving apaging message for the incoming call from the calling party, andcontrolling the speech recognition and character display operation. 2.The apparatus of claim 1, wherein upon receipt of the speech recognitionnotification request message, the base station recognizes that thecalled party mobile phone is in the speech recognition and characterdisplay mode and transmits a corresponding voice information message tothe calling party, wherein the corresponding voice information messageindicates a status of the called party mobile phone and directs thecalling party to leave a message.
 3. The apparatus of claim 1, whereinthe controller transmits the speech recognition notification requestmessage to the base station, if predetermined key data has been receivedby the called party mobile phone, upon receiving the paging message forthe incoming call.
 4. A method for speech recognition and characterdisplaying in a called party mobile phone for receiving an incoming callfrom a calling party in a mobile telecommunication system, comprisingthe steps of: receiving a paging message for an incoming call from acalling terminal; determining if the called party mobile terminal is ina speech recognition and character display mode; transmitting a speechrecognition notification request message to a base station, if thecalled party mobile terminal is in the speech recognition and characterdisplay mode; receiving a voice signal from the calling party throughthe base station; converting the received voice signal to voice datausing speech recognition; converting the voice data to character data;and displaying the converted character data on a display of the calledparty mobile phone.
 5. The method of claim 4, wherein upon receipt ofthe speech recognition notification request message, the base stationrecognizes that the called party mobile phone is in the speechrecognition and character display mode and transmits a correspondingvoice information message to a corresponding caller the calling party,wherein the corresponding voice information message indicates a statusof the called party mobile phone and directs the calling party to leavea message.
 6. The method of claim 4, further comprising the steps of:determining whether predetermined key data has been received from akeypad of the mobile terminal of the called party; transmitting thespeech recognition notification request message to the base station;receiving the voice signal from the calling party through the basestation; converting the received voice signal to voice data using speechrecognition; converting the voice data to character data; and displayingthe converted character data on the display of the mobile phone.
 7. Anotification system for notifying a called party of an incoming callfrom a calling party through voice recognition in a mobiletelecommunication system, comprising: a memory for storing aspeech/character conversion table for converting voice data to characterdata; a speech recognition and character conversion unit for convertinga voice signal received from the calling party through a base stationinto character data based on the conversion table; a controller fordetermining whether a voice recognition mode has been chosen by thecalled party and informing the base station if the called party haschosen the voice recognition mode, wherein the controller displays theconverted character data as a text message on a display of a mobileterminal of the called party.
 8. The notification system of claim 7,further comprising: an RF module for processing an RF signal receivedfrom the base station or to be transmitted to the base station by radio.9. The notification system of claim 7, wherein the controller allows thecalled party to choose the voice recognition mode by displaying thevoice recognition mode in a menu on the display.
 10. The notificationsystem of claim 7, wherein the base station transmits a voiceinformation message about the voice recognition mode to the callingparty if the called party has chosen the voice recognition mode.
 11. Thenotification system of claim 10, wherein the speech recognition andcharacter conversion unit is located within the mobile terminal of thecalled party.
 12. The notification system of claim 11, wherein the basestation accepts a voice message from the calling party and transmits thevoice message as the voice signal to the mobile terminal of the calledparty.
 13. The notification system of claim 7, wherein the speechrecognition and character conversion unit is located within the basestation.